Novel cathodes consisting of la3ni2o7+δ mixed with ba0.5sr0.5co0.8fe0.2o3-δ for proton-conductive solid oxide fuel cells (p-sofcs)

This work studied on the development of novel cathodes for proton-conductive solid oxide fuel cells (p-SOFCs) made of powders La3Ni2O7+δ (LNO2) mixed with Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF). The cathodes were constructed by a skeleton of LNO2 whose surface coated by BSCF in the ratio (in wt.%) of LNO2/BSCF varying in 15/85, 30/70, 50/50, 75/25 (denote as LN15, LN30, LN50, and LN75, respectively). The skeleton was responsible for carrier conduction and air transportation; the BSCF coating was responsible for catalytic oxygen reduction reaction (ORR). Nascent powders directly collected from combustion were subject to examination by scanning electron microscope (SEM) and X-ray diffractometer (XRD) and further calcination. Well crystalized with highly pure powders obtained post their calcination at 900 °C. Performing the button cells by means of I-V testing at 600, 700 and 800°C, the data of maximum power density (P_m) depicted the order LN75 < BSCF < LN15 < LN30< LN50 regardless of temperatures. Among all the specimens, LN50 could be the best cathode candidate for P-SOFCs.